Armature winding apparatus



Feb.

1964 J. PALS 3,121,539

ARMATURE WINDING APPARATUS Filed Feb. 24, 1959 y E 12 I 22 27 A 13 2830 48 INVENTOR JAN FA' 5 BY 5M AGENT United States Patent 3,121,539 ARMATURE WINDING APPARATUS Jan Pals, Drachten, Netherlands, assignor to North American Philips Company, Inc., New York, N.Y., a

corporation of Delaware Filed Feb. 24, 1959, Ser. No. 795,222 Claims priority, application Netherlands Apr. 21, 1958 Claims. (Cl. 242-13) Winding machines are known for providing the slots of rotors of small collector motors with drum windings, in which the center line of the rotor with its axis rotates in a plane during the winding operation and, after terminating each winding and prior to beginning the next winding, a wire loop of the winding wire of a given length is brought outside the rotor, and the rotor is subsequently set to a next position by rotation about its longitudinal axis. After terminating the winding, the wire loops passed to the outside, are one by one torsioned and subsequently secured to the collector. In practice, it has been found that these loops often get entangled so that it is difficult to secure them correctly to the collector laminations. These wire loops might engage round fixed pins so as to exactly remain in position but this entails the serious disadvantage that the loop itself is tensioned during winding which may cause the loop to be opened or snapped off.

The present invention has for its object to obviate these disadvantages, in a device for providing the slots of rotors of small collector motors with drum windings, in which the center line of the rotor with its axis rotates in a plane during the winding operation and, after terminating each slot winding and prior to the beginning of the next slot winding, a wire loop of the winding wire, of given length, is brought outside the rotor and the rotor is subsequently set to a new position by rotation about its longitudinal axis. The loop is attached to means following the rotor but being stationary with respect to the latter which means comprise as many fixed pins (to which the loops are attached), as the rotor has slots, in such manner that each pin extends in line with a slot, while each pin is associated with a resilient extending substantially parallel to the pin and having a stop closing the aperture between the pin and the rod. The means following the rotor also carries structure to displace a resilient rod just after starting the winding operation so as to urge the stop away from the fixed pin. Upon hooking the loops around these fixed pins so that they rest on the stops, the stop may be removed after winding a few turns of the slot winding so that the loop is fastened, thus avoiding over tensioning of the loop. The loops remain loosely engaged around the pins to preclude entanglement.

In one form of the invention, the fixed pins are arranged along the perimeter of a cone and the resilient rods are movable in slots of a second conical member located within the pins. This form has the advantage that the loop slides easily along the pin and sufiicient space is available for the movement of the resilient rods.

In a further form of the invention, a dished member has an edge, the inside diameter of which exceeds the enveloping curve of the ends of the fixed pins, except with respect to one pin which lies outside this edge due to a deformation of the latter; a pawl associated with the dished member is radially movable relatively to the rotor shaft and one end which is located between the end of a 3,121,539 Patented Feb. 18, 1964 "ice fixed pin and the end of the rod co-acting therewith, which pawl has a fulcrum in the dished member and is springloaded in a manner such that the stop normally engages the fixed pin, provision further being made of a control member for turning the pawl so as to force away the resilient rod carrying the stop. This yields a compact structure.

The pawl is controllable in many different ways, for example, electrically by means of relays, but it is simpler for the control member to consist of a spring-loaded weight having an edge behind the end of which the pawl engages, the latters position being controlled by rotation of the device.

In order to prevent premature lifting of the pawl, a winding machine with a device in which the control member is a weight, can be provided with means known per se for winding the beginning of each slot winding at a low initial speed, whereas the remaining turns of the slot winding are wound at full speed, thereby ensuring that the pawl is controlled by the weight only after winding a few turns so that the loop has a firm hold.

The loops may be hooked by hand around the fixed pins, but it is advantageous to effect this mechanically. For this purpose, in a further form of the invention, a winding machine with a device described before is characterized in that provision is made of a wire guide by which, after terminating each winding, the wire is hooked around the end of the fixed pin associated with an incompletely wound slot.

In order that the invention may be readily carried into effect, an example will now be described in detail with reference to the accompanying drawing, in which:

FIG. 1 is a side View of a rotor with twelve slots to be provided with drum windings, one winding of which is shown.

FIG. 2 shows diagrammatically a rotor arrangement on a machine for winding the rotor.

FIG. 3 is a detailed, partly cut away view of the winding device A taken generally along line III-Ill of FIG. 2. The section through the rotor being taken along line IIIIII of FIG. 1.

FIG. 4 is an end view taken along line IV-IV of FIG. 3.

FIG. 5 is an end view taken along line VV of FIG. 3.

In FIG. 1, the reference numeral 1 designates a rotor made up of separate laminations and having twelve slots 2 evenly distributed along the perimeter. These slots are to be provided with drum windings, one of which is shown and designated by 3. Prior to the beginning of each winding, it is necessary to form a loop, the two parts of which are later twisted and secured to a collector lamination. This loop, which is designated by 4 in FIG. 2, is preferably held by pins lest the loops get entangled and become unequal in length. The winding mechanism itself, as shown in FIG. 2, comprises a base plate 5 which is secured to a shaft 6 and adapted to rotate. The base plate carries two holders 7 between which a shaft 8 carrying the rotor 1 is clamped. On rotation of the shaft 6 a wire 9 guided in known manner (not shown) enters the slots so as to form a drum winding. The loop 4, held as shown schematically in FIG. 2, is tensioned in winding so that, as has been found in practice, the wire of the loop 4 is likely to be opened or snap ofi.

As may be seen from FIG. 3 a conical member 10 is seated on the shaft 8 and clamped to it by means of a set screw 11. This member comprises twelve diverging stationary pins 12. The member likewise comprises twelve resilient pins 13 each having a stop 14 fitting in a cavity of the rods 12. Secured to the member 1% is a conical member 15 with radial slots 16 engaged by the resilient rods 13. The device further comprises a shaft 8a. By means of a shoulder 17, a nut 18 and a key 19 this shaft is firmly mounted in the support 7 which in turn is rigidly secured to the base 5. The shaft 8a has a thicker part 29 fitting in a corresponding cavity 21 of the member 15. By means of a key 23 a dished member 22 is rigidly secured to the shaft 8a. This dished member 22 (see also FIG. 5) has an edge 24, the inner perimeter of which has a radius exceeding the enveloping curve of the ends of the stationary pins 12. This edge 24 has a re-entrant part 25 so that one pin 12 is outside the edge. The member 22 possesses a pawl 26 adapted for rotation about a pin 27 and loaded by a spring 28. The point 29 of the pawl 26 exactly fits between a pin 12 and a rod 13. A weight 39 has a bevelled edge 31 and is freely movable or slideable on theshaft 16. The tail of the pawl 26 engages the bevelled edge 31. A weak spring 32 holds the weight in position. For clarity, a space is shown between the dished member 22 and the pins 12. Actually, the point of the pawl 29 is located between a rod 13 and a pin 12 during the winding operation. Finally, provision is made of a retor positioning pawl 33 (shown in FIG. 2) which holds the rotor during the winding operation and has a pointed end 34 as shown in FIG. 6.

The assembly operates as follows:

When the rotor 1 is to be wound the beginning of the wire is provisionally secured to the member 16, for example by means of a hook 35 of the member in, and a complete slot winding is wound. Subsequently the rotor is rotated, the wire is engaged or looped around a rod 12 so that it rests against the stop 14, and the wire is then introduced into the next slot. The pawl 33 likewise engages the next slot. Subsequently, the base 5 is turned and the next slot winding is wound. When the base 5 has a sufiicient speed the weight 30 moves against the action of spring 32 toward the shoulder 17. As a result, the pawl 25 turns about the fulcrum 27 and the nose 29 of the pawl urges the resilient rod 13 inwards. The loop end of the wire is then allowed to slide past the stop 14 and is no longer held in tensioned so as to prevent breakage of the wire. However, the wire loops are still held between the rod 13 and the pin 12 so that entanglement of the loops is avoided. After the winding operation of one set of slots, a loop is hooked on a next pin 12 which remains on a next stop 14 until the associated rod 13 is forced away by the pawl 26. Hooking the wire around the pins 12 is allowed by the re-entrant part 25 of the edge 24, of dished member 22, as a result of which each next pin comes free from this edge or into the re-entrant part so as to permit the loop to be easily hooked on the pin 12. After winding the rotor completely, the clamping screw 11 is loosened. By means of a suitable tool all the resilient rods 13 are shifted towards the shaft and subsequently the member 10 is urged towards the rotor so as to permit the wire a loops to he slipped over the ends of the pins 12, these loops occupying the correct position for securing to a collector.

On commencing each slot winding, it is advisable to cause the machine, including the above described device, to operate slowly for a few seconds lest the weight 3%) be shifted prior to the loop 4 being held in the slot by the overlying windings. It has, however been found that this is not always necessary if the spring 32 is in correct relationship with the mass of the weight 39. Otherwise, the pawl 26 may alternatively be operated in a different manner, for example by means of an electric relay. This however, requires sliding rings.

When using wire guides known per se, it is naturally possible to hook the wire ends on the pins 12 not by hand but mechanically. This permits the rotor to be wound in one continuous operation. Mechanically looping the wire on the wrong pin is largely eliminated with the device according to the invention, since each time only one pin 12 is present around which a loop may be hooked.

The device is particularly intended for winding small rotors, but it will be appreciated that it may also be used for winding coils comprising tappings.

What is claimed is: 1. Apparatus for winding a wire about a rotor having a plurality of slots comprising, in combination, means to rotate the rotor transversely about its axis, and means fixed relative to said rotor to retain a wire loop of th winding wire of given length outside the rotor, said latter means comprising a plurality of fixed pins each of which corresponds to a slot in the rotor, a resilient rod extending substantially parallel to each said fixed pin, a stop member engaging the wire loop and connected to the resilient rod and extending across the space between the pin and the rod, and pawl means to displace the resilient rod just after the start of winding whereby the stop is urged away from the fixed pin and the wire loop released.

2. Apparatus for winding a wire about a rotor having a plurality of slots comprising, in combination, means to rotate the rotor transversely about its axis and means fixed relative to said rotor to retain a wire loop of the winding wire of given length outside the rotor, said latter means comprising a conical member, a plurality of fixed pins secured to the rim of said conical member each of which corresponds to a slot in the rotor, a resiiient rod extending substantially parallel to each fixed pin and moveable in the slotted portion of the conical member, a stop member engaging the wire loop and connected to the resilient rod and extending across the space between the pin and the rod, and pawl means to displace the resilient rod just after the start of winding whereby the stop is urged away from the fixed pin and the wire loop released.

3. Apparatus for winding :1 wire about a rotor having a pluraiity of slots comprising, in combination, means to rotate the rotor transversely about its axis and means fixed relative to said rotor to retain a wire loop of the winding wire of given length outside the rotor, said latter means comprising a plurality of fixed pins, each of which corresponds to a slot in the rotor, a resilient rod extending sub stantially parallel to each said fixed pin, a stop member engaging the wire loop and connected to the resilient rod and extending across the space between the pin and the rod, a disc-shaped member having an edge with a reentrant portion, the edge of said disc-shaped member having a diameter exceeding the diameter of a curve enveloping the ends of said fixed pins except for said reentrant portion whereby one of said pins is located outside said edge, a pawl member moveable radially relative to the rotor shaft, one end of said pawl member being located between one of said fixed pins and a corresponding resilient rod coacting therewith, said pawl having a fulcrum point in said disc-shaped member, resilient means urging the said stop member into engagement with the fixed pin, and a control member for actuating the pawl and disengaging the stop member of the resilient rod from the fixed pin. 4. A device as claimed in claim 3, in which the control member is a spring-loaded weight with an edge behind which the end of the pawl engages.

5. Apparatus for winding rotors of the commutator type comprising an assembly including a rotor having a shaft and a plurality of slots, 7

a plurality of loop engaging means included in said assembly for holding conductor loops brought out from each of the rotor slots for subsequent connection to commutator segments,

said loop engaging means having a stop portion for holding said conductor loops temporarily taut, and a rod portion for holding said conductor loops separated and unstressed during Winding of said rotor,

means mounting said loop engaging means on said shaft adiacent one end of said rotor,

a movable Weight member included in said assembly, said Weight member being mounted in said assembly for movement in response to rotation of said assembly about an axis normal to the longitudinal axis of said rotor,

and means included in said assembly cooperative with said loop engaging means and actuated by movement References Cited in the file of this patent UNITED STATES PATENTS Gomory Mar. 6, 1923 Dewey Apr. 8, 1930 'Eaton Dec. 6, 1932 Farmer Mar. 3, 1959 

1. APPARATUS FOR WINDING A WIRE ABOUT A ROTOR HAVING A PLURALITY OF SLOTS COMPRISING, IN COMBINATION, MEANS TO ROTATE THE ROTOR TRANSVERSELY ABOUT ITS AXIS, AND MEANS FIXED RELATIVE TO SAID ROTOR TO RETAIN A WIRE LOOP OF THE WINDING WIRE OF GIVEN LENGTH OUTSIDE THE ROTOR, SAID LATTER MEANS COMPRISING A PLURALITY OF FIXED PINS EACH OF WHICH CORRESPONDS TO A SLOT IN THE ROTOR, A RESILIENT ROD EXTENDING SUBSTANTIALLY PARALLEL TO EACH SAID FIXED PIN, A 